More generally, tan and cotan, sin and cos, sec and csc "swap" complementary angles. That is, if and are the two non-right angles in a right triangle, then [tex]tan(\theta)= cot(\phi), , [tex], and . And, of course, those two angles add to (did I get it right, Prove It?).

More generally, tan and cotan, sin and cos, sec and csc "swap" complementary angles. That is, if and are the two non-right angles in a right triangle, then [tex]tan(\theta)= cot(\phi), , [tex], and . And, of course, those two angles add to (did I get it right, Prove It?).

I just meant because is the ratio of the circumference to the diameter of a circle, while is the symbol for product :P